A preferred field of application is the production of antennas for radio-frequency identification systems (RFID antennas), flexible printed circuit boards or other multilayer elements that can be produced by lamination and have conductive structures, for example, for electrical circuits by using flexible substrates in strip form in a roller-to-roller process.
In the production of electrical or electronic components for mass applications, it is endeavored to provide the desired electrical functionality in good quality with the lowest possible production costs. In one class of production methods, a laminate is produced as an intermediate product by a conductor foil, in particular a metal foil, being connected to the substrate by a layer of adhesive lying in between. Subsequently, the conductor foil is structured by being severed by a suitable separating process, for example, laser cutting, punching and the like at the boundaries of those regions intended to later form the conductor structure. In many cases, this involves creating relatively large pieces of foil that do not belong to the end product and accordingly have to be removed from the intermediate product before further method steps can follow.
EP 0 790 123 B1 and corresponding DE 697 34 328 T2 describe a method of producing a laminate from a patterned metal foil and a substrate in which a metal foil web is laminated onto a substrate by an adhesive being introduced between the metal foil and the substrate in a predetermined pattern. The pattern defines regions in which adhesive is present and regions in which no adhesive is present. Subsequently, the metal foil is cut into a pattern corresponding to the boundaries of the regions containing the adhesive. The cutting may take place, for example, by rotational punching or laser cutting. Those regions of metal foil not adhesively attached to the substrate by the adhesive are subsequently removed, for example, by suction.
WO 2009/118455 A1 discloses other methods of the generic type. In one variant of that method, a conductor foil is selectively fastened to the substrate material, desired regions of the end product that form the final conductor structure and narrow regions between the conductive regions of the end product being connected to the substrate by an adhesive, and laterally extended regions of the foil intended to be removed later remaining largely unconnected to the substrate, such that they are at most connected to the substrate in a peripheral region removed in a later structuring step. Subsequently, the conductor foil is structured by material removal, namely removing material from narrow regions between the desired regions of the conductor structure and the outer periphery of the larger foil regions intended to be removed from the piece later to create the conductor structure. After that, the pieces of foil no longer fastened to the substrate are removed since the peripheral region of these pieces of foil that was removed from the outer periphery of these pieces of foil during the structuring operation no longer securely holds the pieces of foil on the substrate.
It could therefore be helpful to provide a method and a system of producing a multilayer element that allow production of high-quality multilayer elements with a high degree of reliability of the process at low production costs.